【摘要】 利用数值模拟方法研究应县木塔的动力特性及其抗震性能。首先从斗拱连接的实际构造出发,建立反映接触传力机制的斗拱节点域计算模型,研究其自身的动力特性,并利用动力特性等效方法将斗拱节点域简化为刚接简化模型和铰接简化模型。然后用简化节点域模型代替实际斗拱节点域建立木塔整体刚接和铰接有限元模型,并对这两个计算模型开展动力特性分析、弹性反应谱分析和时程分析。最后根据计算结果和相关研究成果对其地震作用下的性能进行评估。结果表明:木塔实测振型和计算振型基本相似,实测前4阶振型周期介于刚接计算模型与铰接计算模型之间;木塔二层明层是木塔的薄弱层;木塔在7度(0.15g)多遇地震作用下将产生严重损坏,二层明层位移角接近木塔倒塌的限值,在设防地震作用下有倒塌的可能。更多还原

【Abstract】 The dynamic characteristics and seismic behaviors of Yingxian Wooden Pagoda was studied by numerical simulation method.Firstly,the dynamic characteristics of the typical buckets was studied using the FEM model considering the contact effect between the elements of the corresponding buckets,in which the complicated bucket was simplified as two kinds of computational models(one called equivalent frame model or another equivalent hinged model) by dynamic characteristic equivalent method.Secondly,two kinds of equivalent computation models of the Wooden Pagoda are established with equivalent frame model or equivalent hinged model replacing the corresponding buckets of the Wooden Pagoda.Based on the two models,the dynamic characteristics analysis,the elastic spectrum analysis and time-history analysis were carried out.Lastly,the seismic behaviors of the Wooden Pagoda was evaluated according to the computational results and related data.The results show that: ① the vibration modes from the computational models are close to those from the test on site and the periods of the first four vibration modes from the test is between those from the two computational models;② the second floor is the weak position of wooden pagoda under earthquake;③ the wooden pagoda would be damaged seriously under 7 degree(0.15g) seismic action,and its corresponding displacement angle of second floor is close to the collapse critical value of wooden pagoda;④ the Wooden Pagoda is likely to collapse under earthquake with its seismic fortification intensity.更多还原